Aminoglycoside antibiotics, for example, streptomycin, kanamycins, gentamicins, tobtamycin, etc. have practically been used as broad spectrum antimicrobials effective against gram-positive, gran-negative and acid-fast bacteria. The aminoglycoside antibiotics, however, are sometimes accompanied by undesired side effect such as nephropathy and deafness. Occurrence of resistant strains against the aminoglycosides is another problem to be solved. It has been attempted to modify such aminoglycoside with a specified group at the 1-amino group in order to improve the antimicrobial activity and relatively decrease the side effects. For instance, amikacin which is prepared by acylation of the 1-amino group of kanamycin A with (S)-4-amino-2-hydroxybutyric acid [Kawaguchi et al, J. Antibiotic, 25, 695 (1972); U.S. Pat. No. 3,781,268 (1973); J, Antibiotic 27, 677 (1974)] and butyrosin which is prepared by acylation of the 1-amino group of ribostamycin with (S)-4-amino-2-hydroxybutyric acid [U.S. Pat. No. 3,541,078] are well known. And besides, an aminoglycoside derivative which is prepared by introduction of (SR)-3-hydroxy-1-pyrrolin-2-yl into the 1-amino group of ribostamycin is published in Carbohydrate Research, 28 (1973), 263 to 280.